The 606 is just too old. Unless it comes to you with every part and accessory you will require, it should be avoided because you are not going to find pieces for it anywhere now. The C35 was a rare effort by Durst to market a low cost enlarger for the entry level consumer market. It usually comes standard as a 35mm only format, although an accessory kit was sold toconvert it to 6x6cm format. You'd never find one of those kits now. Alternative - Consider an M600, Comes standard for 45mm and 6x6cm. It shares lens boards with several other, newer models and it is readily available (on ebay). It would be more expensive in the US, about $100 - 125. A much more long term unit compared to the C35. Also, if so inclined, it takes a colorhead which can still be found. If you want a 35mm only model, look at the M35. If you want 35mm and B&W only, look for an Omega B22,